Reject (Non-Standard) Coconut Fruit for Bioavtur / SAF Production

The international civil aviation organization (ICAO) has included non-standard coconuts on the ICAO positive list – ICAO document – ​​CORSIA Default Life Cycle Emissions Values ​​for CORSIA Eligible Fuels, 6th Edition on October 28 2024. Non-standard coconuts include very small old coconuts, already sprouted, starting to rot or mold and those that are broken. Based on data from a number of research studies, the number of non-standard coconuts in Indonesia is estimated to reach 30% of Indonesia's coconut production. Non-standard coconut is also a potential raw material for the production of sustainable aviation fuel (SAF).

Basically the raw materials sought for SAF bioavtur are pure triglycerides and long chain carbon chains. This is due to the volatility of jet fuel, the preferred components are hydrocarbons in the C10 to C15 paraffin range. Furthermore, to meet the freezing point specifications (-47oC), this paraffin must have many branches to reach this low freezing point. This means that bio-avtur or SAF must have carbon atom bonds or C bonds in the C10-C15 range, and in this range palm kernel oil and coconut oil are most suitable because of the high composition of lauric acid which consists of 12 C atoms.

With the high laurate content in palm kernel oil and coconut oil, the yield will be high because the oil content is in the bio-avtur range, namely C10 - C15. This is different if you use vegetable oil with a longer carbon chain, for example CPO, nyamplung oil or canola / rapeseed oil. If you use long chain vegetable oil, the yield will be small and an extra cracking process is needed to increase the bioavtur or SAF yield.

And because the raw material used for bioavtur / SAF is oil from coconut flesh, the coconut water can be used to produce nata de coco or bottled coconut water, then coconut shells for the production of charcoal, charcoal briquettes or activated charcoal, husk for fuel to produce energy and potassium-rich ash for fertilizer or for planting media (cocopeat) and cocofiber. Meanwhile, coconut cake are used for animal feed.

Blue Economy & Bioeconomy – Seaweed, Coconut and Nyamplung

With the second longest coastline in the world, located on the equator so it has a tropical climate and the largest coconut producer in the world, maintaining and continuing to develop coconuts is very important and strategic for Indonesia, especially since Indonesia has long been famous as the land of waving coconut trees. The productive life of coconut trees is also very long, namely 60 years, so they can be passed down across generations. The nyamplung tree, which is easy to grow and is often found in coastal areas, should also be developed, as well as the potential for seaweed. With the development of the times to carry out decarbonization in various sectors of life, especially the use of renewable energy, coconut, nyamplung and seaweed can be an effective solution.

Coconut oil, like palm kernel oil (PKO), has a high lauric acid content, so it is very suitable for the production of Sustainable Aviation Fuel (SAF). Currently, Indonesia is planning to increase SAF production from palm oil, namely palm kernel oil, to 3% this year (2026). This policy was accelerated to support the aviation sector's decarbonization targets. Palm kernel oil production is around 5 million tons/year with the main uses currently being very diverse, including the food industry (margarine, chocolate, cakes), cosmetics (soap, shampoo, lipstick), oleochemicals (fatty acids, glycerol), to renewable energy (SAF) - still in the early stages, as well as non-food products such as lubricants. while the potential for coconut oil is 2.9 million tons with the main uses being cooking (cooking oil), processed food industry (biscuits, margarine, ice cream), cosmetics (soap, shampoo, moisturizer), health (consumed directly as Virgin Coconut Oil (VCO)) and pharmaceuticals (ointment base), skin/hair care and oleochemicals. Why coconut oil and palm kernel oil are very suitable for SAF production, read more details here.

In addition to the potential raw material for SAF from coconut, the international civil aviation organization (ICAO) has included non-standard coconut in the ICAO positive list - ICAO document - CORSIA Default Life Cycle Emissions Values for CORSIA Eligible Fuels, 6th Edition on October 28 20024. Non-standard coconut includes very small old coconuts, already sprouted, starting to rot or become moldy and those that are broken. Based on data from a number of research studies, the number of non-standard coconuts in Indonesia is estimated to reach 30% of Indonesia's coconut production.

Regarding coconuts, the government should limit or prohibit exports of round coconuts. This will not only hinder the domestic coconut processing industry but also more specifically the development of SAF. Apart from that, efforts to replant coconut plantations must also be carried out. The area of ​​coconut plantations that must be replanted currently reaches hundreds of thousands of hectares, such as in Riau alone with a coconut plantation area of ​​426,579 hectares (11.4% of the plantation area in the province, read more details here). 72 thousand hectares of coconuts need to be replanted, while the replanting speed is very low so coconut productivity continues to decline. Meanwhile, nyamplung trees and seaweed require socialization and real action so that they can meet production targets and expectations.

Meanwhile, nyamplung oil can be used for biodiesel / FAME production. From the government's plan to increase the biodiesel mixture from B-40 to B-50, this means requiring almost 60 million tons/year of vegetable oil, especially palm oil. Meanwhile, currently crude palm oil or CPO production is around 50 million tons/year and increasing 20% ​​or to 60 million tons/year is certainly not easy. Moreover, currently the expansion of palm oil plantations (extensification) is in the sharp public spotlight with widespread public attention. A number of natural disasters, especially the Sumatran floods, which have claimed the lives of thousands of people, with the extensification of palm oil plantations as the suspect, have made it increasingly difficult to increase palm oil production through expanding this land. And indeed land expansion (extensification) must always be in the corridor of sustainability, so that palm oil can be a blessing and not a disaster.

Nyamplung trees with productivity almost the same as palm oil trees are very interesting to develop for biodiesel production or more practically adding 10 million tons / year to reach the B-50 proportion. Along Indonesia's very long coastline, there are locations for coconut and nyamplung plantations. Apart from that, seaweed from its waste is also a potential raw material for renewable energy, both ethanol, biodiesel and SAF.

Meanwhile, from the seaweed sector, apart from the production of agar, carrageenan and alginate which are widely used for food products, biofuel can be produced from seaweed waste. Seaweed industry waste can reach 65-75% of the fresh raw materials processed. This very large amount is often wasted without further use which can increase added value. Because solid seaweed waste contains a high percentage of cellulose and only a small amount of lignin, this waste has the potential to be processed into bioethanol and sustainable aviation fuel (SAF). 

The process route, namely ATJ or alcohol to jet fuel, can be used to produce sustainable aviation fuel (SAF). Meanwhile, seaweed waste is usually disposed of in landfills, which can cause unpleasant odor problems. Specifications for industrial waste from the E. cottonii species are 3.66% water content; ash 36.84%; protein 1.78%; carbohydrates 11.36%; 0% cellulose; hemicellulose 12.86%; lignin 0%. Meanwhile, industrial waste specifications from the species Gracilaria sp. and Gelidium sp.: cellulose 26.92%; hemicellulose 16.11%; lignin 15.38%; ash 16.72%; water content 12.94%; NaCl 3.77%. 

After their productive life is over or ends, the coconut trees and nyamplung trees are cut down. Coconut tree trunks and nyamplung trees are very suitable for building wood used for housing. This will add economic value and is a necessity that will continue to be needed. In fact, efforts to improve the quality of wood can also be done by engineering the wood material, such as with CLT (cross laminated timber) and so on.

And like palm oil, both coconut and nyamplung also produce shells. Just as palm kernel shells can be used for fuel, so coconut shells and nyamplung shells as well. Even palm kernel shells or known as PKS (palm kernel shell) are the main competitors of wood pellets in the global biomass fuel market. However, because the quality of coconut shells is better or more suitable for the production of charcoal briquettes and activated carbon, coconut shells are generally carbonized or made into charcoal. Charcoal is an intermediate product or raw material for charcoal briquettes and activated carbon. Read more details about the production of activated carbon from coconut shells here. Meanwhile, because nyamplung shells are not widely produced, their use is still limited, but if the quantities are large, such as the production of palm kernel shells, then it could be like palm kernel shells, or perhaps also like the use of coconut shells.

Apart from that, both the production and extraction of coconut oil and nyamplung oil will produce cake. Coconut cake and palm oil cake can be used as animal feed, but nyamplung cake requires additional processing so that it is non-toxic and safe for animal feed. The development of a blue economy on the Indonesian sea coast should be an important concern as an environmentally friendly economic solution that suits the conditions and potential of Indonesian society and is in line with the global community's concerns about decarbonization as mitigation for climate change and global warming. Apart from also supporting food and feed security. 

Exploring the Market for Bioenergy and Biocarbon Products in the Era of Global Decarbonization

The demand to lower the earth's temperature by reducing greenhouse gas concentrations through various global agreements such as the Paris Agreement and Net Zero Emissions (NZE) 2050, followed by technical follow-up through decarbonization for various sectors and industries, continues. This is the driving force for increasing renewable fuels, especially those based on biomass or bioenergy products, which have been implemented, but are experiencing dynamics in the form of fluctuations in demand and prices. Bioenergy, with its numerous advantages and uniqueness as a renewable energy, cannot be replaced in this era of global decarbonization, even though in the near future some subsidies for biomass fuels or bioenergy will be eliminated.

This is closely related to a government's decarbonization priorities, particularly among the various emerging options. Bioenergy products can vary in quality, but all have their own market segments within specific industries. Furthermore, the sustainability of biomass sources is also a crucial aspect in the business and use of bioenergy, and is strictly enforced by standards such as GGL, FSC, SBP, RED III, and SURE. Industrial groups such as cement, iron and steel, chemicals, and even the aviation sector, which previously relied 100% on fossil fuels or energy sources, are gradually shifting to renewable energy sources.

Bioenergy products such as industrial wood pellets and industrial wood briquettes are primarily marketed in the power generation industry and as fuel for industrial boilers. Industrial wood pellets are very popular and are produced in larger quantities than industrial wood briquettes. Due to the elimination of subsidies and the implementation of sustainability certification, biomass fuel producers are required to produce better quality products using environmentally friendly and accountable raw materials. This also applies to bioenergy derived from agricultural waste, which generally lacks sustainability certification at large production capacities.

Biomass power plants operating near carbon neutrality can then be upgraded to carbon-negative operation, or atmospheric carbon dioxide removal (CDR) by adding carbon dioxide capture and storage (CCS) equipment. Biomass power plants equipped with CCS devices are popularly called BECCS (Bio-Energy Carbon Capture and Storage). It is predicted that the BECCS era will not be far off, and countries with biomass power plants can easily upgrade to BECCS. Expensive CCS equipment and low carbon credit revenue from CDR remain current obstacles. Japan, with around 300 biomass power plants, has great potential to upgrade to BECCS. And as a biomass power plant, the need for fuel will always be needed, such as wood pellets and PKS (palm kernel shells). For more details, read here.

One successful example of BECCS is the Stockholm Exergi BECCS project. BECCS illustrates how existing biomass power generation infrastructure can be leveraged to generate sustainable carbon dioxide sequestration. The Stockholm project, based on sustainably sourced biomass fuel, secured one of the world’s largest carbon sequestration deals with Microsoft, a significant contract worth SEK 500 million (~89 billion rupiah). Their model integrates carbon capture with a district heating system, maximizing energy efficiency while achieving permanent carbon dioxide sequestration.

Similarly, several other large industries, such as cement, aluminum, and chemicals, are also gradually decarbonizing. Biomass fuels, such as wood pellets and agricultural/plantation waste like palm kernel shells (PKS), are preferred in this sector. Besides their high energy content, these biomass fuels are more affordable than derivatives like torrefied biomass and charcoal/biochar. With the gradual transition or decarbonization of these industries, the demand for biomass fuels will also continue to increase.

Meanwhile, biocarbon products such as torrified biomass (biocoal) and carbonized biomass (biochar/charcoal) are starting to attract attention and are expected to reach mass production levels in the near future. Power plants typically favor biocoal due to its higher energy content, hydrophobicity, which allows it to be stored in open areas like coal, and ease of crushing (high grindability index). Meanwhile, biochar/charcoal, especially in the iron and steel industry, is highly suitable for producing low-carbon steel and even green steel. The reductant for blast furnaces, which previously used coke from coal, can be replaced by charcoal or biochar. Charcoal or biochar with high purity (fixed carbon >85%) and low impurities are required for blast furnace reductants. For more details on this, please read here and here.

Meanwhile, the use of biomass for sustainable aviation fuel or SAF (Sustainable Aviation Fuel) is also very possible. This is because currently there are three leading production processes for SAF production: HEFA (Hydro-processed Esters and Fatty Acids), FT (Fischer-Tropsch), and ATJ (Alcohol to Jet Fuel). Biomass through thermochemical processes, namely in FT (Fischer-Tropsch) and biochemical processes, namely in ATJ (Alcohol to Jet Fuel), can be used as raw material or feedstock. Meanwhile, the raw material or feedstock for the HEFA process is not solid biomass but vegetable oil, used cooking oil, animal fats, and so on. So the broad application of biomass as various important energy sources in the era of global decarbonization is a driving force for biomass production both through the forestry sector and sustainable agriculture/plantations.

 

Biochar for Sustainable Coconut Productivity

Coconut fiber accounts for 30%, or about a third, of the weight of a coconut. This material is generally left in plantations and remains largely unused, potentially polluting the environment. With Indonesian coconut production reaching approximately 2.9 million tons per year, or 15.13 million coconuts per year, the potential for coconut fiber production is enormous, amounting to approximately 1 million wet tons (average moisture content of 60%) or 500,000 dry tons (10%) of moisture.

The volume of coconut husk is largely unaffected by the government's recent policy of exporting whole coconuts, particularly to China, as shown in this video. Many coconut-based industries are struggling to secure raw material supplies, even leading to factory closures. Industries such as dessicated coconut, coconut milk, coconut shell charcoal and charcoal briquettes, and activated carbon are severely impacted by this policy. Selling processed or industrialized coconut products would clearly add greater value and create jobs. Developed countries also export finished or semi-finished goods, not raw materials.

The industrialization of coconut-based products is crucial. Like palm oil, coconut processing products are primarily used for food products. Utilization for energy or biofuel is also very possible, such as for sustainable aviation fuel or SAF (Sustainable Aviation Fuel). Even for palm oil, the use of biofuel is in the form of a mandatory blend of palm oil from CPO (crude palm oil) in biodiesel 40% this year and is being reviewed to be 50% (B50) by 2026, as well as palm oil from PKO (palm kernel oil) for a 3% blend for sustainable aviation fuel or SAF in 2026. The main content of coconut oil is lauric acid, the same as palm kernel oil or PKO. Lauric acid consisting of 12 carbon atoms (C) or MCFA (medium chain fatty acids) is very suitable for the use of sustainable aviation fuel or SAF must have a carbon atom bond or C bond in the range of C10-C15, for more details read here.

 

Coconut productivity continues to decline due to inadequate or slow replanting programs. A similar situation is also experienced by oil palms (for more details, read here), and this presents a unique obstacle. The area of ​​coconut plantations that needs replanting also reaches tens or even hundreds of thousands of hectares. For example, in Riau Province, the target is 43,388 hectares of coconut plantations to be rejuvenated by 2025. In addition to increasing coconut productivity through the use of superior seeds, intensification is also necessary. High coconut productivity and high selling prices are driving this replanting.

Utilizing or producing biochar from coconut fiber is a solution to increase sustainable coconut productivity. Biochar can also significantly support organic coconut plantations. Although coconut trees are generally not fertilized adequately or even not at all, they still bear fruit. Biochar increases fertilizer use efficiency because biochar acts as a slow-release fertilizer agent. Regarding fertilization, coconuts differ significantly from oil palms, which require fertilization for fruiting and are highly dependent on chemical fertilizers. In fact, fertilization is the highest cost component in oil palm plantations. Organic coconut products produce desirable derivative products with high selling prices.

The potential revenue from carbon credits is also very attractive. To obtain carbon credits, or BCR (Biochar Carbon Removal), the biochar application, including the production process, must be verified by a carbon standards agency. Carbon standards agencies such as Puro Earth, Verra, and CSI have developed methodologies that biochar producers must follow to obtain these credits. 

Palm Kernel Oil (PKO) and Coconut Oil (CCO) for Bio-Avtur (SAF)

Bio-avtur or SAF (Sustainable Aviation Fuel) will be the only decarbonization scenario in the aviation sector for the next few decades. The three leading production processes for SAF production are HEFA, FT and ATJ. And of the three processes, the HEFA process is the most efficient and most competitive at present, predicted to survive until 2030. The raw materials or feedstock for the HEFA process are mainly vegetable oil, used cooking oil, animal fat and so on. The HEFA process has also been approved by ASTM for use as aviation fuel (bio-jet fuel) based on ASTM D7566-14. In 2011 the latest version of the standard was published that allows up to 50% of HEFA aviation fuel products to be added to conventional jet fuel or petroleum-based fuel (avtur). ASTM itself, as an entity, does not have the authority or drive the development or qualification process of a new SAF technology, but only creates a framework, process, and repository that is the basis for the industry to create test methods, specifications, classifications, guidelines, and practices for their own needs.

Bio-avtur or SAF must have characteristics similar to conventional jet fuel so that it can be used anywhere in the world. Jet A fuel is primarily used in the US and jet A1 fuel is used in the rest of the world. The fuels are interchangeable. The main difference between the two types is that Jet A1 has a lower freeze point (-47oC, vs. -40oC) and usually has a static quenching additive (SDA) added to help reduce static buildup in the fuel during flight. Jet A1 is the fuel of choice for intercontinental flights. Given the volatility of jet fuel, the preferred components are hydrocarbons in the C10 to C15 paraffin range. Furthermore, to meet the freeze point specification (-47oC), these paraffins must be highly branched to achieve such a low freeze point. This means that bio-avtur or SAF must have carbon atom bonds or C bonds in the C10-C15 range, and in this range palm kernel oil (PKO) and coconut oil (CCO) are most suitable due to their high lauric acid composition which consists of 12 C atoms.

HVO / HEFA - SPK (Hydro-processed Esters and Fatty Acids-Synthesized paraffinic kerosene) is a renewable paraffin with combustion properties similar to other renewable paraffins such as Fischer-Tropsch fluids, produced by biomass gasification and chemical synthesis. HVO / HEFA can be produced in dedicated facilities producing 100% HVO, or it can be co-processed with fossil fuels in petroleum oil refineries. In co-processing, a bio-based feedstock of typically 5-10% is blended with the fossil feedstock. The HVO / HEFA process in addition to renewable diesel (which is different from biodiesel – FAME) can also be modified to produce bio-avtur / SAF for jet fuel applications. AltAir Fuels supplies HVO / HEFA based SAF and produces approximately 13 million liters per year.

HEFA is produced by hydrogenation and hydrocracking of vegetable oils and animal fats using hydrogen and catalysts at high temperature and pressure. In this hydrotreating process, oxygen is released from the feedstock consisting of triglycerides and / or fatty acids. This will produce straight chain hydrocarbons (paraffins) with various properties and molecular sizes depending on the characteristics of the raw materials and the operating conditions of the process being carried out. With the high lauric content in palm kernel oil (PKO) and coconut oil (CCO), the yield will be high because the oil content is in the bio-avtur range, namely C10 - C15. This is different if you use vegetable oil with a longer carbon chain, such as CPO, calophyllum inophyllum oil or canola oil. If you use vegetable oil with a long chain, the yield will be small and an extra cracking process is needed to increase the yield of bioavtur or SAF.

This conversion usually goes through two stages, namely hydrotreatment followed by hydrocracking/isomerization. This hydrotreatment process is usually carried out at a temperature of 300 -390 C and for triglyceride treatment, propane is usually produced as a by-product. The more hydrogen is added, the less propane is produced. The final product of the straight-chain hydrocarbon can be adjusted according to the type of fuel, for example for bio-avtur or bio jet fuel or SAF, namely by isomerization and the cracking process. The hydrogen used in HEFA production currently mostly comes from fossil sources or blue hydrogen. The catalyst for this can be a simple refinery hydro-processing catalyst. This catalyst can be adjusted to isomerize the paraffin chain to lower the melting point of the product. If necessary, a second isomerization stage is used to carry out this task in order to achieve the required jet fuel cold flow properties, namely Jet A or Jet A-1.

Currently, Pertamina (Indonesia's state-owned oil company) has succeeded in producing bio-avtur or SAF from palm kernel oil or PKO processing, namely refined bleached deodorized palm kernel oil (RBDPKO) called bioavtur J2.4 or containing vegetable oil ingredients in the form of RBDPKO 2.4%. The production of this bioavtur is carried out through the Hydrotreated Esters and Fatty Acids (HEFA) co-processing method and has a capacity of 9,000 barrels per day. The J.24 bioavtur has successfully undergone commercial flight tests on a Boeing 737-800 NG aircraft owned by PT Garuda Indonesia (Persero) Tbk. (GIAA) on October 4, 2023. And for the future, apart from the quantity aspect, namely the portion of vegetable oil (PKO) is larger, even the use of other vegetable oils such as coconut oil (CCO), CPO oil, calophyllum inophyllum oil and so on, it is also hoped that the quality of bioavtur will also improve. In addition, there are also plans from other institutions, namely the production of biovatur or SAF from coconut oil in collaboration with Japan.

In the aviation fuel industry, ASTM serves as the international standard for jet fuel quality, and plays a critical role in ensuring the safety, quality, and reliability of Sustainable Aviation Fuels (SAF). ASTM establishes requirements for criteria such as composition, volatility, fluidity, combustion, corrosion, thermal stability, contaminants, and additives, among others, to ensure that fuels are compatible when blended. ASTM International (American Society for Testing and Materials) is an international organization that develops technical standards for a wide range of materials, products, processes, systems, and services. Jet fuels must meet stringent quality specifications to be eligible for use in the aviation industry.

There are several ASTM standards related to this jet fuel, namely first, ASTM D1655: This is a conventional jet fuel specification that establishes requirements for Jet A and Jet A-1 produced from petroleum. This specification has been used globally by the aviation industry since 1959 to ensure the availability of safe and consistent jet fuel for all aircraft. Second, ASTM D4054: This ASTM standard practice defines the scope of fuel, rig, and engine property testing that should be considered when evaluating new synthetic jet fuels. This practice also describes the overall evaluation process and the important role of engine and aircraft manufacturers in ensuring a good jet fuel safety record is maintained with these new fuels. Third, ASTM D7566 Pathway: As per ASTM D4054, the pathway includes definitions of synthetic jet fuel blending components as defined by: permitted feedstocks; conversion processes and their attributes; and the final characteristics of the pure components. All of this is detailed in both the body of D7655 and its Appendices. The pathway will also define blending requirements.

In order for a new SAF production line to be included in D7566, it must undergo extensive testing to determine the maximum blend ratio with conventional jet fuel and demonstrate that the blend is suitable for its intended purpose. This procedure is outlined in ASTM D4054, ‘Standard Practice for Evaluation of New Aviation Turbine Fuels and Fuel Additives’.

Each batch of jet fuel needs to be certified before it can be used. While conventional jet fuel is certified as D1655 fuel (or a derivative), pure SAF is certified to the stringent specification requirements set out in Appendix D7566 which relates to the SAF production line. D7566 certified SAF is blended with conventional jet fuel to the maximum allowable blend ratio. The blended SAF is then certified to the D7566 blend requirements, and thus automatically receives D1655 certification, making it fully Jet A/A-1 compliant (‘drop-in fuel’) and ready for use in existing jet fuel infrastructure and equipment. In short, ASTM is vital to the aviation fuel industry as it is the basis for international standards for the quality of jet fuels, and SAF in particular.

PAO and UCO Become Bio-Jet Fuel

Decarbonization has entered all lines including the air transportation sector. Aviation fuel must also gradually shift from fossil fuels to sustainable renewable fuels. However, decarbonization in this sector is still slow, namely currently only around 0.01% of the use of sustainable renewable fuels or SAF (Sustainable Aviation Fuel) globally for these aircraft. These barriers include technological maturity or technological readiness, certification for SAF conversion or production process routes, scale up and commercialization, price gaps with fossil fuels, and competition with biofuels in the land transportation sector. The Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) has initiated a reduction in GHG emissions for global aviation. Using the 2019 baseline, it is estimated that around 2.5 billion tonnes of CO2 emissions need to be offset / reduced in the 2021-2035 period to achieve carbon neutral growth. CORSIA also plans its implementation in three phases, namely the pilot phase in 2021-2023, the first phase in 2024-2026 and the second phase in 2027-2035. Participation of member countries is voluntary in the first two phases (2021-2026) and mandatory in the 2027 phase and beyond, except for the least developed countries, small developing countries and landlocked countries.

Until now, HVO / HEFA - SPK (Hydro-processed Esters and Fatty Acids-Synthesized paraffinic kerosene) technology using vegetable oil including waste oil is the only technology that is most ready for the conversion or production of SAF. Currently, the technology readiness level (TRL) and feedstock readiness level (FRL) are at level 9, meaning that it is the most ready among other conversion technology routes. One of the advantages of HVO technology is the flexibility of using various feedstocks / raw materials so that waste oil such as PAO or mico from palm oil mill ponds and also used cooking oil or used cooking oil or UCO are also very potential to be converted into SAF with HVO technology. But in fact, even though HVO technology can directly produce SAF, most of the HVO technology is used for the production of diesel engine fuel for land transportation or commonly called green diesel or renewable diesel. Green diesel or renewable diesel is different from biodiesel or FAME-based biodiesel which is produced by the transesterification process. And green diesel or renewable diesel from HVO also has a number of advantages compared to FAME based biodiesel.

HVO production is also not a new technology. Globally, there are a number of large-capacity commercial HVO plants that use vegetable oil as raw material. The largest plants are Neste in Rotterdam and Singapore with a capacity of 1.28 billion liters per year and Diamond Green Diesel in Louisiana with a capacity of 1.04 billion liters per year. HVO production is closer to petroleum refining technology than conventional diesel production. This is why oil and gas companies may be more interested in developing it than palm oil companies or conventional biodiesel companies. Palm oil mills have raw materials / feedstock, while oil and gas companies may be more relevant to downstream development because of the readiness to adapt technology and develop end products.

HVO is produced by hydrogenation and hydrocracking of vegetable oils and animal fats using hydrogen and catalysts at high temperature and pressure. In this hydrotreating process, oxygen is released from the feedstock consisting of triglycerides and / or fatty acids. This will produce straight chain hydrocarbons (paraffins) with various properties and molecular sizes depending on the characteristics of the raw materials and the operating conditions of the process being carried out. This conversion usually goes through two stages, namely hydrotreatment followed by hydrocracking / isomerization. This hydrotreatment process is usually carried out at a temperature of 300 -390 C and for triglyceride treatment, propane is usually produced as a by-product. The final product of straight chain hydrocarbons can be adjusted according to certain fuel types such as bio jet fuel or SAF. Currently HVO is the third most common biofuel in the world after ethanol and FAME based biodiesel.

PAO is produced as waste or by-product of palm oil mills. PAO will always be produced because palm oil mills cannot have an efficiency level of 100% and the less efficient the palm oil mill, the more oil becomes waste or by-product in the form of PAO. It is estimated that there are currently 1 million tons of PAO in Indonesia and 0.5 million liters in Malaysia or a total of 1.5 million tons. As for UCO or used cooking oil with the use of cooking oil reaching 1.55 million tons/year assuming 10% can be recovered as used cooking oil or UCO, 155 thousand tons/year are produced. In addition to being part of the effort to overcome waste both in palm oil mills and households that pollute the environment, the production of SAF or bio-jet fuel has also contributed to the decarbonization of the air transportation sector. With HVO / HEFA technology that is able to process waste oil such as PAO and UCO, the more PAO and UCO that can be processed, the better.

SBE Pyrolysis: A Profitable Waste Management Solution

Spent Bleaching Earth (SBE) which is solid waste produced from the bleaching process in the CPO processing industry into cooking oil and oleochemicals is increasing along with the production of palm oil derivative products or downstream palm oil industries such as cooking oil and oleochemicals. The amount of bleaching earth used generally ranges from 0.5-2.0% of the total CPO refined, depending on the quality of the CPO to be processed in the refining process. SBE is included in category 2 hazardous toxic material (B3) waste from specific sources with waste code B413. SBE is categorized as hazardous toxic material (B3) waste because it contains high oil and has characteristics that are flammable and corrosive. SBE can be categorized as non-B3 waste if its oil content is below 3%.

The classification of SBE status as hazardous toxic material (B3) waste in Indonesia is different from the status of SBE in Malaysia, which is also the second largest palm oil producer in the world. SBE waste produced by the Malaysian refinery industry is not classified as B3 waste but is still categorized as solid waste from refinery factories whose processing is regulated in the Solid Waste Regulation (SWR) so that the waste can be reused into products with high economic value.

According to the Indonesian Vegetable Oil Industry Association (GIMNI, 2021), with a refinery capacity of palm oil/CPO between 600 tons to 2,500 tons per day, and assuming the use of bleaching earth (BE) of 1%-2%, the average will produce 6-50 tons of SBE per day. And according to the Directorate General of Waste Management, Toxic and Hazardous Materials (PSLB3) of the Ministry of Environment and Forestry, the SBE produced from the vegetable oil refining process in Indonesia in 2019 reached 779 thousand tons. Of that amount, 51.47% (401 thousand tons) of SBE was processed, while the remaining 48.39% (378 thousand tons) was stored or stockpiled. A very large amount and has the potential to pollute the environment.

SBE has an oil content of around 20-40%, so it has the potential to be utilized. In addition, SBE also contains color, gum, metals namely Silica, Aluminum oxide, Ferrioxide, Magnesia, other metals and water. Basically, SBE processing is done by separating oil from its solids. The separated oil can then be used as raw material for biodiesel and even aircraft fuel (bio-jet fuel) such as POME / PAO and UCO. With the amount of unprocessed SBE reaching around 378 thousand tons per year, the potential oil that can be extracted reaches around 115 thousand tons per year.

With pyrolysis, the process of separating solid and liquid fractions from SBE is easy to do, as well as oil recovery can be maximized, as well as SBE becomes non-hazardous toxic material (non-B3) waste because its oil content is below 3%. More specifically, with continuous pyrolysis, the volume of SBE waste reaching 50 tons per day in the CPO refinery unit can be easily done. The large potential economic value that can be obtained from the utilization of SBE is a shame if it is not optimized. The market opportunity for processed products from SBE waste is also expected to be bright in the future, along with the development of market preferences that demand the availability of eco-friendly and sustainable products.